Commit 38a72dac authored by Kent Overstreet's avatar Kent Overstreet Committed by Jens Axboe
Browse files

block: Add bio_copy_data_iter(), zero_fill_bio_iter() 



Add versions that take bvec_iter args instead of using bio->bi_iter - to
be used by bcachefs.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent f4f8154a

block/bio.c

+24 −20
Original line number Diff line number Diff line
@@ -530,20 +530,20 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, unsigned int nr_iovecs, 
}

EXPORT_SYMBOL(bio_alloc_bioset);



void zero_fill_bio(struct bio *bio)

void zero_fill_bio_iter(struct bio *bio, struct bvec_iter start)

{

	unsigned long flags;

	struct bio_vec bv;

	struct bvec_iter iter;



	bio_for_each_segment(bv, bio, iter) {

	__bio_for_each_segment(bv, bio, iter, start) {

		char *data = bvec_kmap_irq(&bv, &flags);

		memset(data, 0, bv.bv_len);

		flush_dcache_page(bv.bv_page);

		bvec_kunmap_irq(data, &flags);

	}

}

EXPORT_SYMBOL(zero_fill_bio);

EXPORT_SYMBOL(zero_fill_bio_iter);



/**

 * bio_put - release a reference to a bio
@@ -971,28 +971,13 @@ void bio_advance(struct bio *bio, unsigned bytes) 
}

EXPORT_SYMBOL(bio_advance);



/**

 * bio_copy_data - copy contents of data buffers from one chain of bios to

 * another

 * @src: source bio list

 * @dst: destination bio list

 *

 * If @src and @dst are single bios, bi_next must be NULL - otherwise, treats

 * @src and @dst as linked lists of bios.

 *

 * Stops when it reaches the end of either @src or @dst - that is, copies

 * min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of bios).

 */

void bio_copy_data(struct bio *dst, struct bio *src)

void bio_copy_data_iter(struct bio *dst, struct bvec_iter dst_iter,

			struct bio *src, struct bvec_iter src_iter)

{

	struct bvec_iter src_iter, dst_iter;

	struct bio_vec src_bv, dst_bv;

	void *src_p, *dst_p;

	unsigned bytes;



	src_iter = src->bi_iter;

	dst_iter = dst->bi_iter;



	while (1) {

		if (!src_iter.bi_size) {

			src = src->bi_next;
@@ -1029,6 +1014,25 @@ void bio_copy_data(struct bio *dst, struct bio *src) 
		bio_advance_iter(dst, &dst_iter, bytes);

	}

}

EXPORT_SYMBOL(bio_copy_data_iter);



/**

 * bio_copy_data - copy contents of data buffers from one chain of bios to

 * another

 * @src: source bio list

 * @dst: destination bio list

 *

 * If @src and @dst are single bios, bi_next must be NULL - otherwise, treats

 * @src and @dst as linked lists of bios.

 *

 * Stops when it reaches the end of either @src or @dst - that is, copies

 * min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of bios).

 */

void bio_copy_data(struct bio *dst, struct bio *src)

{

	bio_copy_data_iter(dst, dst->bi_iter,

			   src, src->bi_iter);

}

EXPORT_SYMBOL(bio_copy_data);



struct bio_map_data {

include/linux/bio.h

+15 −3
Original line number Diff line number Diff line
@@ -67,8 +67,12 @@ 


#define bio_multiple_segments(bio)				\

	((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)

#define bio_sectors(bio)	((bio)->bi_iter.bi_size >> 9)

#define bio_end_sector(bio)	((bio)->bi_iter.bi_sector + bio_sectors((bio)))



#define bvec_iter_sectors(iter)	((iter).bi_size >> 9)

#define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))



#define bio_sectors(bio)	bvec_iter_sectors((bio)->bi_iter)

#define bio_end_sector(bio)	bvec_iter_end_sector((bio)->bi_iter)



/*

 * Return the data direction, READ or WRITE.
@@ -501,6 +505,8 @@ static inline void bio_flush_dcache_pages(struct bio *bi) 
}

#endif



extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter dst_iter,

			       struct bio *src, struct bvec_iter src_iter);

extern void bio_copy_data(struct bio *dst, struct bio *src);

extern void bio_free_pages(struct bio *bio);
@@ -509,7 +515,13 @@ extern struct bio *bio_copy_user_iov(struct request_queue *, 
				     struct iov_iter *,

				     gfp_t);

extern int bio_uncopy_user(struct bio *);

void zero_fill_bio(struct bio *bio);

void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);



static inline void zero_fill_bio(struct bio *bio)

{

	zero_fill_bio_iter(bio, bio->bi_iter);

}



extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);

extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);

extern unsigned int bvec_nr_vecs(unsigned short idx);